Standard molar enthalpies of formation of 5- and 6-nitroindazole

The present work reports the experimental determination of the standard (p ^o = 0.1 MPa) molar enthalpies of formation in the condensed and gaseous phases, at T = 298.15 K, of 5- and 6-nitroindazole. These results were derived from the measurements of the standard molar energies of combustion, using a static bomb calorimeter and from the standard molar enthalpies of sublimation derived by the application of Clausius–Clapeyron to the temperature dependence of the vapour pressures measured by the Knudsen effusion technique. The results are interpreted in terms of the energetic contributions of the nitro groups in the different positions of the aromatic ring.